Tracking RFID objects with integrated communication link

ABSTRACT

A wireless system ( 101 ) includes a plurality of objects ( 106 ). The wireless system includes a controller  102  and a radio frequency identification (RFID) read-write (RW) device ( 103, 104, 105 ). Each of the objects includes an RFED device ( 107 ) and a transceiver ( 108 ). An object and methods of tracking objects are also disclosed.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. provisional application Ser.No. 60/691,130 filed Jun. 16, 2005, which is incorporated herein byreference.

Tracking or monitoring of an object provides a history (location andtime) of the object's movements. This tracking can be widely applied toa variety of objects and the information garnered in the tracking can beexceedingly useful. For example, it is often desirable to maintaininformation on the whereabouts of a package in transit. Moreover, it maybe imperative to be able to ascertain the location of a patient in ahospital.

Certain techniques have been implemented to ascertain the location of anobject. One technique attempts to determine the location of an objectusing data of the signal strength of a signal transmitted from theobject. However, this method can result in inaccuracy in objectlocation. For example, the signal strength can vary due to channelvariations over time, even when the object is stationary. Moreover,there may be physical obstacles between the object and a central device.These physical obstacles can result in signal attenuation andnon-uniform path losses. In general, the determination of the locationof an object based on the signal strength from an object received at thecentral device, by itself, is not a reliable method due to theinconsistent correlation between the object's location and the signalstrength.

Another technique used to determine the location of an object includesthe use of a radio frequency (RF) identification (ID) system. An RFIDsystem normally includes a plurality of RFID tagged objects (alsoreferred to as RFID objects) and a network of RFID read/write (RW)devices each in a particular fixed location. The RFID objectscommunicate with the RW devices when the objects are in relatively closeproximity to the RW devices. In a known system, this communicationincludes the transmission of an ID signal from the particular RFIDobject to the particular RW device. The proximity of an RFID object tothe known location of the RW device sets the location of the RFID objectat a particular moment in time. Once ascertained, the RW device mayrecord the time that the RFID object communicated, and thus store thelocation of a particular RFID device at a particular time. The RWdevices are linked to a central device (e.g., a location trackingdevice) by either a wired or wireless link. During operation, thecentral device can access the data from each of the RW devices in itsnetwork to gather the location information of the RFID tagged objects.

While the RFID-based system noted above does provide locationinformation on RFID objects, there are drawbacks to such systems.Notably, this system requires a network of RW devices, which must beadapted to communicate with the central device to provide the data fromthe RFID objects. This network can be cumbersome and expensive.Moreover, when an RFID object is outside the range of a RW device, itslocation is lost unless and until the object travels within the range ofanother RW device. Thus, all areas excepting those in rather closeproximity of the RW devices are ‘blackout’ areas. Finally, if for somereason the communications between the RW devices and the system fails,the tracking function and the link to the RFID objects is lost.

What is needed, therefore, is a method and apparatus for determining thelocation of objects that overcome at least the shortcomings of the knownmethods and apparati described above.

In accordance with an example embodiment, a wireless system includes acontroller and a radio frequency identification read-write (RFID RW)device. The wireless system also includes a plurality of objects, eachincluding a radio frequency identification (RFID) device adapted toreceive information from the RFID RW device. In addition, each objectincludes a transceiver adapted to transmit information to and receiveinformation from the controller.

In accordance with another example embodiment, an object includes aradio frequency identification (RFID) device, which is adapted toreceive information from an RFID RW device. The object also includes atransceiver, which is coupled to the RFID device, wherein thetransceiver is adapted to transmit information to and receiveinformation from a controller, or a tracking application device, orboth.

In accordance with another example embodiment, a method of trackingobjects includes providing a plurality of RFID RW devices in a wirelessnetwork; providing an RFID device in each of the objects; transmittingdata from the RFID RW devices to the objects; providing a transceiver ineach of the objects; and transmitting the data from the objects to acontroller, or to a tracking application device, or both.

The example embodiments are best understood from the following detaileddescription when read with the accompanying drawing figures. It isemphasized that the various features are not necessarily drawn to scale.In fact, the dimensions may be arbitrarily increased or decreased forclarity of discussion. Wherever applicable and practical, like referencenumerals refer to like elements.

FIG. 1 is a conceptual diagram of a wireless system in accordance withan example embodiment.

FIG. 2 a is block diagram of an object in accordance with an exampleembodiment.

FIG. 2 b is a block diagram of an object in accordance with an exampleembodiment.

FIG. 3 is a flow chart of a method of determining the location ofobjects in accordance with an example embodiment.

FIG. 4 is a flow chart of a method of determining the location ofobjects network in accordance with an example embodiment.

In the following detailed description, for purposes of explanation andnot limitation, example embodiments disclosing specific details are setforth in order to provide a thorough understanding of an embodimentaccording to the present teachings. However, it will be apparent to onehaving ordinary skill in the art having had the benefit of the presentdisclosure that other embodiments according to the present teachingsthat depart from the specific details disclosed herein remain within thescope of the appended claims. Moreover, descriptions of well-knownapparati and methods may be omitted so as to not obscure the descriptionof the example embodiments. Such methods and apparati are clearly withinthe scope of the present teachings.

The terms ‘a’ or ‘an’, as used herein are defined as one or more thanone. The term ‘plurality’ as used herein is defined as two or more thantwo. The term ‘coupled’ is defined herein as connected to (e.g.,electrically), although not necessarily directly, and not necessarilymechanically.

FIG. 1 is a conceptual diagram of a wireless system 101 in accordancewith an example embodiment. Illustratively, the wireless system 101 is awireless local area network (WLAN). The system 101 includes a centralcontrol site (controller) 102. In addition, the system 101 includes atleast one RFID RW device (RW). In a specific embodiment, the systemincludes a first RW device 103, a second RW device 104 and an nth(n=integer) RW device 105. Notably, the RFID RW devices 103-105 arestand-alone units that are not coupled (or otherwise networked) to oneanother or to the controller 102. In a specific embodiment, the RWdevices 103-105 are in fixed locations, while in another specificembodiment, the RW device 103-105 may be readily moved. In either ofthese embodiments, the location of the RW devices is programmed into amemory (not shown) in the RW device or is known a priori by the trackingapplication. In yet another specific embodiment, the RFID RW devices103-105 are mobile or are adapted to follow a trajectory. In such anembodiment, the whereabouts of the RFID RW devices 103-105 may beascertained or calculated by known methods. For example, the RFID RWdevices' location may be ascertained by a global positioning system(GPS).

The system 101 also includes at least one object 106, which includes anRFID device 107 and a transceiver 108. In a specific embodiment, thetransceiver 108 is a WLAN device, which is adapted to transmitinformation to or receive information from the controller 102 or otherdevices in the WLAN. Illustratively, the RFID device 107, or thetransceiver 108, or both, are coupled to or are integrated into theobject 106. In addition, each object 106 includes an RFID device 107 anda transceiver 108. Notably, the object(s) 106 do not include GPSdevices. Moreover, the RFID device 107 and the transceiver 108 may sharea common memory, or a communication link, or both.

In an example embodiment, the system 101 includes a trackingapplication. The tracking application enables monitoring of the pathtaken by the object(s) 106 in the system 101 over time. In a specificembodiment, the tracking application is effected via a trackingapplication device 110. In the embodiment shown in FIG. 1, the trackingapplication device 110 is separate from the controller 102. The trackingapplication device may communicate with the controller 102 in a wirelessmanner (e.g., via the WLAN) and thus may be a station in the network.Alternatively, the tracking application device 110 may communicate withthe controller 102 via a wired connection. In yet another exampleembodiment, the tracking application device 110 is a component of thecontroller 102, and is thus integral thereto.

The information 109 provided to the tracking application device 110 fromthe object(s) 106 is compiled into tracking information 111, which isoptionally stored in the tracking application device 100. In a specificembodiment, the tracking application device is implemented in hardwareand software necessary to calculate the path of the object(s) 106 overtime and uses the information 111 to effect this calculation. To meetthis desired end, the traffic application device 110 may include amicroprocessor or an application specific integrated circuit (ASIC) andsuitable software to calculate the path of an object 106 over time, aswell as other transit related information. As the hardware and softwarerequired to effect the path calculations and other transit relatedinformation is within the purview of one of ordinary skill in the arthaving had the benefit of the present disclosure, such details of thehardware and software are not included.

The tracking application provided by the tracking application device 110may be useful in a variety of settings. For example, the object(s) 106may be a package in transit by a shipper. The path of the package may begarnered by the tracking application device 110, and may be in responseto queries from the device 110 input by a user interested in thewhereabouts of the package over time. It is emphasized that this ismerely illustrative of the tracking application device 110 and trackinginformation 111.

In specific embodiments where the system 101 is a WLAN, communicationsbetween the controller 102 (e.g., an access point (AP)), or the trackingapplication device 110, or both, other devices in the wireless system101 and the object 106 (via the transceiver 108) may be realized with avariety of known wireless communications apparati and methods. Forexample, the communications between the object 106 and the controller102 may be in accordance with: IEEE 802.11 and its progeny or IEEE802.15; or known mobile cellular telephone networks; or known RFchannel-based communications (e.g., two-way messaging); or DigitalEnhanced Cordless Telecommunications (DECT); or Bluetooth; or GlobalSystem for Mobile communications (GSM); or known infra-redcommunications. Notably, if the controller 102 were part of a system incompliance with IEEE 802.15, it would be a piconet controller. As thesecommunications methods and apparati are known to one of ordinary skillin the art, details thereof are omitted in order to avoid obscuring thedescription of example embodiments. The apparati and methods may beimplemented in hardware and software within the purview of one ofordinary skill in the art.

Moreover, the networking between the controller 102, the trackingapplication device 110, the object(s) 106 (via the transceiver 108), andother devices in the system 101 may be adapted to function in accordancea variety of communications protocols, including, but not limited to:Time Division Multiple Access (TDMA); or Code Division Multiple Access(CDMA); or Carrier Sense Multiple Access (CSMA); or CSMA with collisionavoidance (CSMA/CA). The apparati and methods may be implemented inhardware and software within the purview of one of ordinary skill in theart.

Communications between the RFID RW devices 103-105 and the RFID device107 of the object 106 is carried out using known RFID apparati andmethods. To this end, radio frequency identification (RFID) is a methodof remotely storing and retrieving data using devices known as RFIDdevices. RFID devices 107 contain antennae and circuitry (not shown)that allows the device to receive and respond to radio-frequency queriesfrom an RFID RW device (e.g., RFID RW devices 103-105). As such, theRFID RW devices 103-105 of the example embodiment are adapted tocommunicate with RFID device(s) 107 of the object(s) 106, but are notadapted to communicate with the controller 102 and are not adapted tocommunicate with the traffic application device 110.

The RFID device 107 may be an active device, including its own powersupply. Alternatively the RFID device 107 or may be a passive device,which uses the energy from received signals to transmit a responsethereto. Moreover, the RFID device 107 may function at a variety offrequencies depending on their application and capabilities. Forexample, the RFID device 107 may function at low frequency (e.g., 125kHz to 134 kHz), or high frequency (13.56 MHz), or UHF (868 MHz to 956MHz), or microwave frequency (e.g. 45 GHz). As the details of RFIDdevices are known, such known details are omitted so as to avoidobscuring the details of example embodiments.

In operation, the object 106 stores information 109. The information 109may include a unique identifier, the RFID RW device ID, which identifiesthe RFID RW device(s), as well as other associated information asinformation 109. This information 109 may be useful in the trackingapplication discussed above. Illustratively, the RFID RW device IDs,ID_(—)1, ID_(—)2 and ID-n, identify the RFID RW devices 103, 104, 105,respectively. The associated information of the RFID RW device(s)103-105 may be their respective spatial coordinates (e.g., x,y,zcoordinates). Optionally, the associated information includes the timethat the object 106 passed within the transmission range of or receiveda transmission from the RFID RW device(s) 103-105 (e.g., t1, t2, . . .). Notably, the object 106 may record the time that it passed withintransmission range and received the RFID RW device ID from theparticular RFID RW device.

In a specific embodiment, the associated information of the RFID RWdevices 103-105 may be that of a particular function. For example, ifthe object 106 were part of or attached to a manufactured product, thenthe associated information may reflect the function that was applied tothe product. For instance, the object 106 could store that the devicehad been inspected by a Quality Inspector having a certain RFID RWdevice. In yet another embodiment, the associated information may belinked to a role in an organization, such as that of an attendingphysician. In yet another example embodiment, the associated informationmay be that of a function such as check-in/check out information at anauto rental facility. In yet another example embodiment the informationmay relate to a function such as a document approval process. As can beappreciated, there are various and sundry embodiments of the RFID RWdevices 103-105 and the associated information they can provide. It isemphasize that the examples given here are merely intended to illustratesome of the many embodiments.

Table 1 further illustrates different types of information 109 that canbe associated with the identity of an RFID RW device and stored on theobject 106. The first column provides the identification of the RFID RWdevice 103-105. The second column provides the locations of the RFID-RWdevices. The third, fourth and fifth columns provide the function, roleor status, respectively. Each of these columns relates to a particularapplication of a group of RFID RW devices 103-105. For example, thethird column, the function, may be an embodiment in which the group ofRFID RW devices 103-105 is part of a tracking scheme in a manufacturingoperation. The forth column may be an embodiment in which theimplementation of the RFID RW devices 103-105 is in a hospital ormedical setting. The fourth column illustrates an embodiment of the RFIDRW devices in a document review process. As noted previously, the typesof information listed in Table 1 are merely illustrative.

TABLE I RFID RW ID Location Function Role Status ID_1 L1 Quality NurseFirst (x1, y1, z1) Inspector Review ID_2 L2 Quality Emergency Second(x2, y2, z2) officer Nurse Review ID_3 L3 Reject ICU Nurse Interim (x3,y3, z3) Handler Review ID_4 L4 Unit Attending Peer (x4, y4, z4)Supervisor Physician Review ID_n Ln Plant Discharge Final (xn, yn, zn)Manager Physician Review

As described more fully herein, the information 109 garnered from theRFID-RW devices 103-105 by the object(s) 106 in the system 101 is storedat the object(s) 106. The information 109 may be retrieved by orotherwise provided to the controller 102. The information 109 may bederived by the controller 102 as described herein.

The information 109 may be provided to the controller 102 in response toa query from the controller 102 to the object(s) 106. Such a query orrequest for information would be carried out in accordance with therelevant communication protocol of the governing the system 101.Alternatively, the information 109 may be provided autonomously by theobject(s) 106. As detailed herein, the autonomous transmission from theobject(s) to the controller 102 may be effected upon achieving certaincriteria, such as time or data limits.

In a specific embodiment, the information 109 is transmitted to thetracking application device 110 via the controller 102. The trackingapplication device 110 may provide a query to an object(s) 106 via thecontroller. For example, the tracking application device 110 maycommunicate the query (or a plurality of queries) to the controller 102,which then relays the query to the appropriate object(s) 106 in thesystem. The object(s) 106 may then transmit the information 109 to thecontroller 102 using the transceiver 108. The controller 102 thenprovides the information 109 to the device 110.

Alternatively, the information 109 may be provided initially to thecontroller 102 and ultimately to the tracking application device 110autonomously by the object(s) 106 at predefined intervals or accordingto predetermined criteria, or both. For example, the predeterminedcriteria may be associated with a number of communications between theobjects(s) 106 and the RFID RW devices 103-105, or may be associatedwith the occurrence of a small number of communications or nocommunications between the object(s) 106 and RFID RW devices 103-105 inthe specified time interval.

In another specific embodiment, the information 109 is transmitteddirectly to the tracking application device 110 by the transceiver 108of the object(s) 106. Like transmissions between the object(s) 106 andthe controller 102, the transmission of information 109 may be inresponse to queries from the tracking application device 110.Alternatively, the information 109 may be provided autonomously from theobject(s) 106 directly to the device 110 at certain intervals oraccording to predetermined criteria, of both. Illustratively, thecommunication between the object(s) and the tracking application device110 is via the wireless system (e.g., WLAN) 101.

FIG. 2 a is a simplified block diagram of the object 106, including theRFID device 107, a WLAN device 201 and a shared memory 202.Illustratively, the RFID device 107, the WLAN device 201 and the sharedmemory 202 are integrated as a unit. As can be appreciated, the object106 is a mobile device. In a specific embodiment the object 106 may be acard (e.g., a smart card), or a cellular telephone, or a mobile radioterminal, or a mobile cellular telephone with an attached data terminal,or a portable computer, or a personal digital assistant (PDA), or atwo-way messaging device a card, or a patient monitoring device, or amerchandise tag.

Regardless of the type of object 106, the WLAN device 201 comprises thehardware and software to realize the transmission and reception ofinformation (voice, or video, or data, or a combination thereof) betweenthe object 106 and the controller 102, or the tracking applicationdevice 110, or both, of the system 101. The hardware and software arewithin the purview of one of ordinary skill in the art, details thereofare omitted in order to avoid obscuring the description of the exampleembodiments. It is emphasized that the WLAN device 201 is a specificembodiment of the transceiver 108 and may function in accordance withmany or all of the protocols referenced previously in conjunction withthe transceiver 108.

As described in detail herein, the shared memory 202 is adapted toreceive data (e.g., information 109) from the RFID device 107 and toprovide these data to the WLAN device 201, which then may transmit thedata to the controller 102 or to the tracking application device 110, orboth. Furthermore, other information (e.g., data) may be received by theWLAN device 201 and stored in the memory 202. For example, the WLANdevice 201 may store voice packets to be transmitted to the controller102 or received from the controller 102 in the memory 202.

FIG. 2 b is a simplified block diagram of the object 106 in accordancewith another example embodiment. The object 106 includes the RFID device107 and the WLAN device 201. The object 106, the RFID device 107 and theWLAN device 201 are substantially the same as those described inconnection with the example embodiment of FIG. 2 a, and the detailsthereof are not repeated. However, the object 106 does not include ashared memory. Rather, a communications link 203 is provided between theRFID device 107 and the WLAN device 201. As detailed herein, as data(e.g., information 109) are garnered by the RFID device 107 or the WLANdevice 201, these data may be provided to the WLAN device 201 or theRFID device 107, respectively. Notably, the communication link 203 maybe on a variety of well known electrical interface technologies,including, but not limited to a serial link, or a bus, or an opticallink, or a Secure Digital Input Output (SDIO) card.

Among other benefits, the system 100 of the example embodimentssubstantially ensures privacy of information 109 of the object(s) 106.In particular, the information 109 is maintained in the memory 202 orotherwise in the object 106 as described in connection with FIGS. 2 aand 2 b. Thus, the information 109 is not accessible except via theobject 106. Furthermore, the object(s) 106 can employ various techniquesto determine what information to transmit whether in response to queriesor autonomously. Furthermore, the object(s) 106 does not necessarilyrespond to each query from every device. For example, the object 106 mayrequire verification of the authenticity of a query from the controller102 or the tracking application device 110 using authentication at thenetwork layer of the wireless system 101 (e.g., at the network layer ofthe WLAN) or using application layer authentication. Theseauthentication methods are specific to the particular type of network(e.g. WLAN 101) or communication protocol and the details of therespective methods are known to one of ordinary skill in the art.

FIG. 3 is a flow chart of a method in accordance with an exampleembodiment. The method is best understood when reviewed in conjunctionwith FIGS. 1-2 b. Notably, in the interest of simplicity, the method isdescribed for one object 106 in the system 101. It is emphasized thatthis is but a specific embodiment, and that the method may beimplemented via a plurality of objects 106 in the system 101. At step301, the method commences with an initialization sequence particular tothe type of system and protocol used. Next, at step 302, the object 106travels in proximity to Location 1 (L1), where the first RW device 103is located. When in range of the first RW device 103, the RFID device107 receives information from the first RW device 103. In a specificembodiment of Step 303, the RFID device 107 receives the location (L1)of the RFID RW device 103 by the RFID RW device ID (ID_(—)1), which isthe code indicative of its unique identity.

In addition, the first RFID RW device 103 may provide the time (t1) ofthe transmission to the RFID device 107. The transmission of the time t1may be foregone, as the time of the reception of the RFID RW device IDand the location may be recorded via a clocking mechanism within theRFID device 107, or other clocking mechanism within the object 106(referred also as a mobile device). The data garnered from the first RWdevice 103 (and internal time clock, if applicable) may then be storedin the shared memory 202, where it can be accessed by the WLAN device201, or accessed and transmitted by the transceiver 108 of the object106. Alternatively, the data may be passed to the WLAN device 201 (ortransceiver 108) by the link 203. In either embodiment, the RFID RWdevice ID of the first RW device 103 and/or its location, and optionallythe time that the object 106 passed in range of the device 103, arerecorded and accessible to the WLAN device 201.

In another specific embodiment, the information 109 may be transmitteddirectly to the tracking application device 110 or to the device 110 viathe controller 102, as described previously.

At step 304, the mobile device passes in proximity of the second RFID RWdevice 104 located at a location L2. The second RFID RW device 104transmits its RFID RW device ID (ID_(—)2) and/or its location, L2, andoptionally the time (t2) of transmission to the object 106. Again, thismay be stored in the shared memory 202, or may be passed to the WLAN 201via the link 203.

At step 305, the object 106 passes in proximity once again to the firstRW device 103. The first RW device 103 transmits its RFID device ID(ID_(—)1), and/or it location L1, and optionally, a time (t3) of thetransmission. The data may then be stored in the shared memory 202 orpassed to the WLAN device 201 via the link 203.

At step 306, the object 106 passes in proximity to the nth RW device105. The nth RW device 105 transmits its RFID RW device ID (ID_n), orits location (Ln), or both, and, optionally, the time of thetransmission (tn) to the RFID device 107. As described previously, thesedata may then be stored by the shared memory 202, or may be transmittedto the WLAN device 201, via the link 203.

As detailed herein, the acquisition of data may continue for a specificperiod of time (e.g., a beacon period, or a service period) as set bythe controller 102, or by the tracking application device 110, or both.

At the end of this period of time, at step 307, the controller 102 mayquery the object 106 for the data (e.g., information 109), whichillustratively includes the location and time information describedpreviously. Alternatively, the tracking application device 110 may querythe object 106 directly or via the controller 102 within an arbitraryperiod of time. Still alternatively, the object 106 may be queried byany another device in its network. Upon receiving the query or queries,and in accordance with the relevant protocol governing the system 101,the WLAN device 201 transmits the information 109 requested to thecontroller 102, or to the tracking application device 110, or both.These data may be retrieved from the shared memory 202, or may beretrieved from an internal memory of the WLAN device 201. Regardless,the object 106 provides the data directly to the controller 102 or thedevice 110, or both. This is in contrast to known RFID systems, wherethe RFID RW devices communicate with a centrally located device and theRFID object is incapable of directly communicating with the centrallylocated device or the tracking application device.

At step 309, the controller 102 or the tracking application device 110,or both compile the path of the object by associating the identity ofeach RFID RW 103-105 with its location and the time. Thereby, thewhereabouts of the object may be readily ascertained over the specifiedperiod of time. After the completion of step 308, the method may repeatbeginning at step 304.

FIG. 4 is a flowchart of a method in accordance with an exampleembodiment. The method of the present example embodiment shares commonsteps 301-306, which are not repeated in so as to avoid obscuring thedescription of the present example embodiment.

At step 401, the object 106 transmits the RFID device IDs for each ofthe RW devices 103-105, and/or the location and, optionally, temporaldata garnered in steps 302-306 to the controller 102. In a specificembodiment, the transmission of the information (e.g., information 109)relating to the movement of the object 106 is autonomous, with theobject 106 transmitting the data at predetermined times. Alternatively,or additionally, the object 106 may transmit the data after receiving acertain amount of data (e.g., information 109). For example, thetransmission may occur after the mobile device has received data from aspecified number of RW devices within the system 101. Stillalternatively, the object 106 may transmit the data according topredetermined criteria. For example, the object 106 may transmit thedata after passing near a specific RW device such as the exit of abuilding. Notably, the predetermined criteria include the occurrence ofa specific event(s). For example, the object 106 may transmit the datain response to external events, such as, a deterioration of the qualityof service (QoS), or a patient's exhibiting abnormal measuredparameters. As such, the example embodiment provides the transmission ofalarming data.

After the data are transmitted to the controller 102, at step 402 thedata are compiled by the controller 102 or by the tracking applicationdevice, or both, in a manner quite similar to that described inconnection with step 309 of the example embodiment of FIG. 3.

The system, devices and methods of the example embodiments providetracking of the object(s) 106 with the system 102. In specificembodiments, the historical data garnered by the object 106 via the RFIDdevice 107 is provided to the tracking application device 110. Thesedata provide the geographical locations or virtual status of the devicesover a period of time, thus providing a tracking capability. In specificembodiments, the object 106 is in direct communication with thecontroller 102 via the transceiver 108. For example, in an embodiment,where the object 106 is a phone, the controller 102 is an AP and thetransceiver 108 is a WLAN device adapted to operate within the networkof AP, the object 106 is in communication with the AP substantiallycontinuously. Thus, if the AP wishes the most recent data of the travelsof the object (e.g., RFID RW IDs of devices 103-105 {ID_(—)1, ID_(—)2,ID_(—)3} and other associated data such as locations {L₁, L₂, L_(n)};and, optionally, timing data), the AP or the tracking application device110 may query the object 106 for these data.

In addition, because the object(s) 106 include transceivers 108 adaptedto operate within the network of the system 101, the tracking of theobject(s) 106 across the network may be carried out in an efficientmanner. For example, the controller 102 could readily ascertain viaknown techniques if an object has traveled outside the range of itsnetwork. Moreover, the geographical data presented to the controller 102provides other benefits. Notably, if after compiling the data on anobject 106, the controller 102 determines that the object 106 is closerto another controller/system, the controller 102 may initiate a hand-offto the neighboring network using known methods. This is particularlybeneficial in managing network capacity in many wireless networks.

In accordance with illustrative embodiments described, a wirelessnetwork includes objects located using RFID devices. One of ordinaryskill in the art appreciates that many variations that are in accordancewith the present teachings are possible and remain within the scope ofthe appended claims. For example, other types of wireless links may beused. These and other variations would become clear to one of ordinaryskill in the art after inspection of the specification, drawings andclaims herein. The invention therefore is not to be restricted exceptwithin the spirit and scope of the appended claims.

The invention claimed is:
 1. A wireless system, comprising: astand-alone radio frequency identification read-write (RFID RW) device;and a plurality of objects, each object including: a radio frequencyidentification (RFID) device adapted to receive information from theRFID RW device; a memory to store said information collected from theRFID RW device when the object is within a known transmission range tosaid RFID RW device; and a transceiver adapted to communicate with acontroller independent of said RFID RW device, said transceivercommunicating said collected information to said controller based atleast on a detection of an event matching at least one criteria; thecontroller; receiving the collected information from corresponding onesof the objects, and determining a path of each of said correspondingones of the objects based on the information collected from said RFID RWdevice, wherein said RFID-RW device is adapted not to transmit to saidcontroller.
 2. The wireless system as recited in claim 1, wherein thecontroller is an access point (AP) of the wireless network.
 3. Thewireless system as recited in claim 1, wherein the information from theRFID RW device is a location of the RFID RW device.
 4. The wirelesssystem as recited in claim 1, wherein the information from the RFID RWdevice includes an identity of the RFD RW device.
 5. The wireless systemas recited in claim 1, wherein the information from the RFID RW deviceincludes at least one of: a time that the RFD device traveled within thetransmission range of the RFID RW device and a time that the RFID devicereceived the transmission from the RFD RW device.
 6. The wireless systemas recited in claim 1, wherein none of the plurality of objects isconnected to a global positioning system (GPS) device.
 7. The wirelesssystem as recited in cairn 1, wherein the memory, the transceiver, theRFID device are integrated within each of the plurality of objects. 8.The wireless system as recited in claim 1, further comprising: thecontroller queries each of the plurality of objects for providing thecollected information.
 9. The wireless system as recited in claim 1,wherein each of the plurality of objects autonomously transmits thecollected information to the controller.
 10. The wireless system asrecited in claim 1, further comprising a tracking application device,which compiles tracking information of each of the plurality of objects.11. The wireless system as recited in claim 10, wherein the trackingapplication device queries each of the plurality of objects for thecollected information.
 12. The wireless system as recited in claim 10,wherein each of the plurality of objects autonomously transmits thecollected information to the tracking application device.
 13. Thewireless system as recited in claim 10, wherein the tracking applicationdevice queries each of the plurality of objects for the collectedinformation via the controller.
 14. The wireless system as recited inclaim 13, wherein each of the plurality of objects transmits thecollected information to the tracking application device in response tothe query.
 15. The wireless system as recited in claim 1, wherein eachof the plurality of objects is adapted to authenticate a request for thecollected information.
 16. The wireless system as recited in claim 1,wherein the plurality of objects are selected from a group comprising:cards, cellular telephones, personal digital assistants (PDAs), mobileradio terminals, cellular phones with data terminals, portablecomputers, or two-way messaging devices, patient monitoring devices,mobile radio terminals, and merchandise tags.
 17. An object, comprising:a radio frequency identification (RFID) device, adapted to receiveinformation from a stand-alone radio frequency identification read-write(RFID RW) device when within a known transmission range of said RFID RWdevice; and a memory to collect and store said information from the RFIDRW device when the object is within the known transmission range to saidRFID RW device; and a transceiver coupled to the memory, wherein thetransceiver is adapted to transmit, independent of said RFID RW device,the collected information stored in said memory to at least one of: acontroller and a tracking application device, wherein said transmissionof said collected information is based at least on a detection of anevent matching at least one criteria and wherein said RFID-RW device isnot in communication with said controller or said tracking applicationdevice.
 18. The object as recited in claim 17, wherein the informationfrom the RFID RW device includes a location of the RFID RW device. 19.The object as recited in claim 17, wherein the information from the RFIDRW device includes an identity of the RFID RW device.
 20. The object asrecited in claim 17, wherein the information from the RFID RW deviceincludes a time that the RFD device traveled within the transmissionrange of, or received the transmission from, the RFID RW device.
 21. Theobject as recited in claim 17, wherein the object does not include a GPSdevice.
 22. The object as recited in claim 17, wherein the object is oneof: a card, a cellular telephone, a personal digital assistant (PDA), amobile radio terminal, a cellular phone with a data terminal, a portablecomputer, a two-way messaging device, a patient monitoring device, and amerchandise tag.
 23. The object as recited in claim 17, wherein the RFIDdevice and the transceiver are integral with the object.
 24. A method oftracking objects, the method comprising: providing a plurality ofstand-alone radio frequency identification read-write (RFID RW) devicesin a wireless network; providing a radio frequency identification (RFID)device in an object; receiving data from the RFID RW devices in theobject when the object is within a transmission range of a correspondingone of the plurality of RFID RW devices; storing and collecting the datareceived from the RFID RW devices in the object; providing a transceiverin the object; and transmitting, independent of said RFID RW device, thecollected data from the object to at least one of: a controller and atracking application device, said transmission of said collected databeing based at least on a detection of an event matching at least onecriteria.
 25. The method as recited in claim 24, wherein the methodfurther comprises, before the transmitting the collected data from theobject, querying the object for the data.
 26. The method as recited inclaim 24, wherein the object is not queried for the collected data. 27.The method as recited in claim 25, wherein the querying is performed bythe controller.
 28. The method as recited in claim 25, wherein thequerying is performed by the tracking application device.
 29. The methodas recited in claim 24, wherein the transceiver is a WLAN device. 30.The method as recited in claim 24, wherein the object is one of: a card,a cellular telephone, a personal digital assistant (PDA), a mobile radioterminal, a cellular phone with a data terminal, a portable computer, atwo-way messaging device, a patient monitoring device, and a merchandisetag.